The present disclosure relates to a light emitting diode and a method for manufacturing the same, and more particularly, to a light emitting diode and a method for manufacturing the same which can improve light emitting efficiency by increasing internal quantum efficiency.
Generally, light emitting diodes (LEDs) emit light of a visible wavelength band or near-infrared and infrared wavelength bands by applying a forward current to a p-n junction formed on a group-III or group-V compound semiconductor wafer. Therefore, they are applied to various fields such as display, communication, instrumentation, control, and lighting.
FIG. 1 is a cross-sectional view of a related art LED. Referring to FIG. 1, the related art LED includes a substrate 10, an n-type semiconductor layer 20, an active layer 30, a p-type semiconductor layer 40, a p-type electrode 50, and an n-type electrode 60.
The n-type semiconductor layer 20, the active layer 30, and the p-type semiconductor layer 40 are sequentially formed on the substrate 10. The p-type electrode 50 is formed on the p-type semiconductor layer 40, and the n-type electrode 60 is formed on an exposed portion of the n-type semiconductor layer 20. The active layer 30 has a quantum well structure where well layers 31 and barrier layers 32 are alternately laminated. The well layers have a low energy band gap and the barrier layers 32 have a higher energy band gap than the well layers 31. Here, the well layers 31 and the barrier layers 32 are alternately laminated once or several times to form a single quantum well structure or a multiple quantum well structure.
Various studies have been continuously conducted to improve an internal quantum efficiency of an LED including an active layer which has a quantum well structure. For example, studies for modifying materials or the number of active layers have been conducted or are currently on the way.